This invention relates to a circuit of a tape recorder, and more particularly to a motor circuit using a D.C. motor.
With a tape recorder, it is generally necessary to take up a magnetic tape at a higher speed for fast feeding and rewinding than for recording and reproduction. Hitherto, the running speed of the magnetic tape has been changed by mechanical means, that is, by selectively using an idler or belt. This mechanical speed-changing system has the drawback that where a tape recorder motor is directly connected to, for example, a battery, the running speed of a magnetic tape more noticeably changes with respect to recording, reproduction, fast feeding and rewinding, according as the energy of the battery is more consumed. To eliminate this drawback, the recently developed tape recorder is provided with a motor control circuit for controlling the drive of a motor. Thus, the motor is connected to the control circuit for recording and reproduction and to a battery for fast feeding and rewinding of a magnetic tape. This system can indeed stabilize the running speed of the magnetic tape for recording and reproduction, but still has the drawback that the rotating velocity of the motor drops in case of fast feeding and rewinding, according as the energy of the battery is more depleted, thereby retarding the takup of the magnetic tape.